Bore-scopes, endoscopes and similar devices for viewing internal body structures and cavities on a video screen utilizing an imaging device and a video camera are well known. Such devices have been used widely in the medical field for viewing internal human tissue and in industry for inspecting the hidden surfaces of various structures.
A typical endoscopic system comprises an endoscopic lens device, a video camera and a video display and/or storage media. The endoscopic device comprises a supporting member, having a forward end to which there is attached an endoscopic tube which enters the internal cavity to be viewed. The endoscopic tube in some cases, but not all (some systems rely on ambient lighting), contains a light guide connected to a light source. e.g. a fiber optic bundle for illuminating the surfaces within the cavity and a lens system for conveying light reflected from these surfaces back to the video camera. The video camera is generally mounted on the supporting member opposite the endoscopic tube. Low level electrical signals developed by the camera (e.g. a CCD Chip) are conveyed through appropriate wires to a signal processing device for creating a video display and/or recording a video image. In some smaller endoscopic systems (e.g. intraoral devices), the endoscopic tube is directly coupled to an SCR camera without an intervening support member.
For infection control, one recent requirement for such devices is that any portion of the device which enters a body cavity must be either discarded or sterilized before reuse. Generally, in previous apparatus, e.g. the intraoral camera system marketed by AcuCam of Canoga Park, Calif., the entire forward end of the endoscopic device, including the light guide and lens system, is detached from the camera for sterilization. Since sterilization, e.g. by autoclaving, is generally time consuming, the dentist would require several expensive lens-fiber optic system members to be on hand for use with subsequent patients. Further, repeated sterilization can degrade or damage the optics and light guides. Hence, a need exists for a device which would allow immediate reuse of a lens-fiber optic system member without delay, damage, or inventory expense associated with the necessity of sterilization.
Another shortcoming of the aforementioned intraoral system is that the same member which is inserted into the oral cavity is held by the user. While the user (dentist) generally wears protective gloves and the portion held is generally a short distance from the inserted portion of the device, it would still be safer for both the user and the patient, that the user should not have to hold that portion of the device at all while in use. Any surface not being exposed directly, either external or internal to the patient's body cavity is considered an environmental surface and is/can be treated by appropriate high level disinfection rather than by sterilization.
A further disadvantage of prior art devices is that the image displayed on the screen is the mirror image of the actual field being observed. In such a system, movement by the manipulator of the device in one direction, e.g. the left, appears as movement in the opposite direction, e.g. the right, on the screen. This often leads to a difficulty of interpretation of orientation and manipulation of the device. It is therefore deskable to employ an imaging system wherein the image viewed on the screen is not reversed with respect to the actual movement of the device by its user.
Still another disadvantage occurring with respect to the prior art intraoral system is that the bulkiness or size of the inserted portion tends to block the vision of the user with respect to the oral cavity and the patient may tend to gag.
Yet another disadvantage of some intraoral systems is that the optical system is not sealed from the oral (or other) cavity thereby requiring sterilization of that member containing that system after each use. Such shortcomings are difficult or impossible to address without potential fatal damage to precision electronics and optics.
The novel device may substantially eliminate the above problems.